Knife adjusting means for paper cutting machines



WILLIAM C. RUPP mflmagwmdg/ ATTORNEYS W. C. RUPP Filed May 31. 1963 KNIFE ADJUSTING MEANS FOR PAPER CUTTING MACHINES Feb. 8, 1966 FIG 4 United States Patent Ohio Filed May 31, 1263, Ser. No. 284,527 2 Claims. (Cl. 83-700) This invention relates generally, as indicated, to a knife adjusting means for paper cutting machines and more particularly to a novel vertical adjustment between the knife blade and the knife bar of cutting machines to ensure that the blade will penetrate completely through a stack of sheets regardless of any stretching in the knife actuating linkage.

In the conventional paper cutting machine well-known in the art, a stack of sheets to be cut is placed upon a table and firmly clamped through operation of a binder clamp prior to bringing down the knife to make the cut. The knife is carried by a knife bar moving in vertically slotted side members and it is generally conventional to provide vertical adjusting screws in the knife bar which engage the upper 'edge surface of the knife blade. In this manner, the knife blade can properly be positioned in the bar prior to final clamping of the blade to the bar. During the setup of the machine, the knife bar is moved to its lowermost position bringing the blade down against a wooden insert in the table. The vertical adjusting screws are then given a further predetermined turn to ensure that the blade will penetrate completely through the stack of sheets despite the stretching of the knife bar actuating linkage during operation of the machine. The blade will then be in a proper vertical position aliowing for such linkage stretching ensuring complete cutting of the stack In smaller machines, however, the blade may be relatively thin, such as A, and this is insufficient to permit accommodation of proper adjusting screws so closely adjacent the surface of the knife bar. Accordingly, on smaller machines, the vertical adjustment feature of the blade is generally omitted, although it is apparent that the problem solved by Such vertical adjustment is still present. Therefore, smaller machines often will not properly completely sever a stack of sheets.

It is accordingly a principal object of the present invention to provide a small paper cutting machine which will completely sever a stack of sheets.

Another principal object is the provision of a knife adjusting means for paper cutting machines permitting even small knives vertically to be adjusted with respect to the knife bar.

Another object is the provision of adjusting screws in the knife bar engaging the clamping bolts rather than the knife blade so that the adjusting screws may be more or less centered in the thickness of the knife bar.

A further object is the provision of an adjusting mechanism for a knife and knife bar which will act more firmly to secure the knife clamping bolts in place.

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

FIG. 1 is a fragmentary side elevation partially broken 3,233,494 Patented Feb. 8, 1966 away and in section of a paper cutting machine provided with a knife and knife bar adjustment in accordance with the present invention, the section through such knife and knife bar being taken substantially on the line 11 of FIG. 2;

FIG. 2 is a front elevation of the knife bar as seen from the right in FIG. 1;

FIG. 3 is a top plan view of such knife bar; and

FIG. 4 is. a vertical section through the knife and knife bar taken substantially on the line 44 of FIG. 2.

Referring now more particularly to the drawing and especially to FIG. 1, the illustrated paper cutting machine embodying the present invention comprises the usual table or bed 1 on which a stack of sheets is adapted to be supported in position for cutting by vertically reciprocable knife blade 2. Such knife 2 is carried by a knife bar 3, each end of which is mounted for such reciprocable vertical movement in vertical slots or ways 4 in side frames 5 and 6 of the machine, the side frame 6 being broken away in FIG. 1. Such side frames are bridged at the top by an upper frame member'7 and extend beneath the table 1 and are secured to the sides of the main table supporting frame 8. The rear portion of the table 1 may be provided with upstanding sides 9 against which the stack of sheets may be positioned for side gauging purposes. An adjustable back gauge, not shown, may also be provided if desired.

Vertical reciprocation of the knife bar and knife blade is obtained by means of vertically reciprocable links 11 mounted within the upstanding side frames 5 and 6; Each link comprises parallel members 12 and 13 carrying therebetween at their upper ends a roller 14. The rollers 14 at each end of the knife bar are confined between shoulders 15 and 16 at the sides of the knife bar as seen in FIG. 2 and knife bar top plate 17 which may be secured to the knife bar by suitable screws threaded into tapped holes 18 and 19' in the top of the knife bar. The knife bar and its top plate thus provide laterally extending horizontal slots in which the rollers 14 are confined.

The lower ends of the members 12 and 13 of each link are joined by two vertically spaced relatively short guide bars 21 and 22 providing a horizontal slideway therebetween for roller 23 on arm 24 secured to rock shaft 25 extending between the side frames 5 and 6. A similar roller and arm connection will be provided from the rock shaft 25 to the pull down link 11 in the opposite side frame. The rock shaft 25 may be oscillated by means of crank 27 pivoted at its distal end to clevis 28 mounted on the rod 29 of piston-cylinder assembly 3%. The blind 'end of the piston-cylinder assembly 30 may be pivoted to the underside of the supporting frame for the table 1 at the rear of the machine. Accordingly, extension of the rod 27 will cause the shaft 25 to rotate in a counterclockwise direction causing the knife blade 2 to descend and conversely, retraction of the piston-cylinder assembly will rotate the rock shaft 25 in a clockwise direction as viewed in FIG. 1 causing the knife blade 2 to be elevated.

The aforementioned binder clamp, removed from FIG. 1 for clarity of illustration may be mounted on the knife bar 3 for reciprocation therewith, being bolted thereto by means of bolts passing through apertures 32 and 33 in the bar 3 as shown in FIG. 2 and through diagonal slots in the binder clamp. Accordingly, when the knife bar descends, the knife and binder clamp (which is constrained to a truly vertical movement between the side frame members 5 and 6) move vertically downwardly together until such clamp engages the top of the stack of sheets. Further downward movement of the clamp is now prevented and the knife bar and knife will be shifted laterally due to the diagonal slots in the binder clamp during further downward movement. The binder clamp mechanism as well as the pull down means illustrated in FIG. 1 do not per se constitute a part of the present invention.

Referring now to FIGS. 2, 3 and 4, in addition to FIG. 1, it will be seen that the knife bar 3 is provided with four vertically elongated slots 35, 36, 37 and 38 through which extend clamping bolts 39 threaded into tapped apertures 40 in the blade 2 corresponding to the slots 35 through 38 in the bar 3. The blade 2, which in the small machine illustrated embodiment may be approximately A thick, fits within a finished ground recess 41 in one face of the bar 3 which terminates in a top shoulder 42. The bottom of the bar 3 may be beveled as indicated at 43 at approximately 45 and the side opposite such recess may be provided with beveled recesses 44 for each of the elongated slots 35 through 38 accommodating the heads 45 of the clamping bolts 39.

The two end slots 35 and 38 are provided with vertical ly extending holes 48 and 49 with the lower portions of such holes being tapped as indicated at 50 and 51 in FIG. 2. Such holes extend completely from the top of the bar 3 to the slots 35 and 38 and corresponding vertically extending apertures may be provided in the bar top plate 17 as indicated at 52 in FIG. 1. Adjusting screws 54 are provided in the threaded portions 50 and 51 of each of the holes and may be brought to bear against the shanks of the clamping bolts 39 in the slots 35 and 38.

In the setup of the machine, the knife blade 2 may be brought down against a wooden bar or stick in groove 60 in the table 1 with the clamping bolts 39 not completely tightened. When the blade 2 is in its lowermost position, the adjusting screws 54 may each be given a further predetermined turn to be sure that the blade is properly contacting the wooden bar in the lowermost position thereof and will thus penetrate completely through a stack of sheets. The horizontal alignment of the blade may also be checked and adjusted in this manner. When the position of the blade 2 is proper with respect to the bar 3, the clamping bolts 39 may be tightened firmly clamping the blade to the bar. The adjusting screws 54 which engage the clamping bolts 39 in the endmost slots 35 and 38 may also act as set screws precluding inadvertent loosening of such endmost clamping bolts. If the screws 54 were brought to bear against the upper end of the blade 2, it can be seen that the apertures therefor would be provided very close .to the rear face of the bar. In the present invention, it can be seen that the adjusting screws are approximately centrally located in the mass of the bar and thus a stronger bar and blade combination is provided. Moreover, the contact between the adjusting screws and clamping bolts which are threaded into the blade 2 has been found to be quite adequate for blade adjusting purposes in such paper cutting ma chines and accordingly even smaller machines may now be provided with such blade adjustment features ensuring the stack to be completely severed.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

1, therefore, particularly point out and distinctly claim as my invention:

1. In a paper cutting machine having a table adapted to support a stack of sheets to be cut, side frame members on the respective sides of said table having vertical guideways therein, a knife bar mounted in said guideways in said side frame members for vertical reciprocation, a knife blade carried by said bar, laterally spaced vertically elongated slots in said knife bar, clamping bolts extending through said slots operative to clamp said blade to such bar, and vertically adjustable means in said knife bar vertically offset from said blade and centrally transversely located within said bar aligned with at least one of said elongated slots operative to engage the clamping bolt therein and vertically to adjust said blade with respect to said bar.

2. In a paper cutting machine having a table adapted to support a stack of sheets to be out, side frame members on the respective sides of said table having vertical guideways therein, a knife bar mounted in said guideways in said side frame members for vertical reciprocation, a knife blade carried by said bar, laterally spaced vertically elongated slots in said knife bar, clamping bolts extending through said slots operative to clamp said blade to such bar, and'means in said knife bar vertically offset from said blade and centrally transversely located within said bar operative vertically to adjust said blade with respect to said bar, said last mentioned means comprising vertically extending adjusting screws operative to engage said clamping bolts thus vertically to position said blade with respect to said bar.

References Cited by the Examiner UNITED STATES PATENTS 596,530 1/1898 McCoy 83-700 645,810 3/1900 Hennessy 15124 848,187 3/1907 Meyers 83700 860,554 7/1907 Meyers 83700 1,515,013 11/1924 DeCosta 83642 2,067,456 1/1937 Meisel 83-700 2,667,922 2/1954 Hill et al 83642 2,707,025 4/1955 Glitsch 83640 WILLIAM W. DYER, JR., Primary Examiner.

HUNTER C. BOURNE, 1a., ANDREW R. JUHASZ,

Examiners. 

1. IN A PAPER CUTTING MACHINE HAVING A TABLE ADAPTED TO SUPPORT A STACK OF SHEETS TO BE CUT, SIDE FRAME MEMBERS ON THE RESPECTIVE SIDES OF SAID TABLE HAVING VERTICAL GUIDEWAYS THEREIN, A KNIFE BAR MOUNTED IN SAID GUIDEWAYS IN SAID SIDE FRAME MEMBERS FOR VERTICAL RECIPROCATION, A KNIFE BLADE CARRIED BY SAID BAR, LATERALLY SPACED VERTICALLY ELONGATED SLOTS IN SAID KNIFE BAR, CLAMPING BOLTS EXTENDING THROUGH SAID SLOTS OPERATIVE TO CLAMP SAID BLADE TO SUCH BAR, AND VERTICALLY ADJUSTABLE MEANS IN SAID KNIFE BAR VERTICALLY OFFSET FROM SAID BLADE AND CENTRALLY TRANS- 